Conventional medical connectors used to connect tubing used in intravenous delivery apparatus include a connector having at least two connector members. One of the connector members typically includes a needle and another of the connector members includes a sealed entry port that is penetratable by the needle to establish fluid communication between the members when the members are connected. The entry port usually comprises resilient material that automatically closes after the withdrawal of the needle.
Typically, the needle is recessed in the cavity of one member so that after termination of the connection, the needle that has been in contact with the patient's blood is not easily contacted by a nurse who is at risk from being stuck by a contaminated needle. Such connectors are disclosed in U.S. Pat. Nos. 4,752,292 and 4,511,359.
These conventional medical connectors however, make no provision preventing a recessed needle from contact with the patient's blood, where the needle could become contaminated.
U.S. Pat. No. 4,511,359 discloses a one-way valve comprised of a biased tubular band fit over a perforated projection permitting pressurized fluid flow in only one direction to keep a fluid connector sterile. The perforated projection therein is impermeable to the introduction of an introducer needle rendering the connector unsuitable for use with a catheter tip. However, the valve structure can be improved upon.
Also, when one of the connector members is fitted with a catheter for placement in the patient's vein and the other connector member is fitted with a movably mounted introducer needle for establishing an opening in the patient's vein to place the catheter, blood flow through the needle and out its other end after a stick indicates whether the venous placement is correct. This blood flow is stopped by disposing of the connector member with the introducer needle and connecting another connector member that is in communication with an intravenous line; however, this exposure to the patient's blood is undesirable.
Conventional needles have a hydrophobic filter membrane to allow air to flow through the hollow of the needle but not blood. Use of such a needle requires that it be removed from the catheter to verify whether a proper insertion in the vein has been effected. With the removal of the needle, blood flows out from the catheter and is contactable by a user.